Sudbury: Rail Town to Regional Capital, by Carl Murray Wallace and Ashley Thomson, indicates that this project was a new building for an existing theater. The book doesn’t say if the new Regent was on the same site as the old one or not.

Hall & Duerr designed at least five theaters. After dissolving his partnership (1919-1926) with B. Kingston Hall, architect Herbert George Duerr established his own practice, and over the next quarter century or so he designed or remodeled at least twenty more theaters, many for the Famous Players chain.